This invention relates to devices which dispense accurate amounts of fluid upon demand, particularly where the fluid is supplied from a pressure-reservoir.
Adhesives have become increasingly popular in various industries as replacements for mechanical fasteners and seals. In the majority of applications, it is critical that the amounts and drop sizes of the adhesives be accurately metered and placed for maximum effect. In some instances, the adhesives are supplied from a pressure reservoir, and are fed through a tube from the reservoir to a dispenser having some sort of valving, which is used to place the adhesive on the work surface. A typical valve release is actuated by a series of interconnections which respond to the ultimate stimulus, for example, manual touch or electrical signal. The difficulty here is the number of parts involved in producing a drop or a line of adhesive; and more parts, the greater likelihood of gradual inaccuracies occurring during use due to wearing out of parts. Although the foregoing emphasizes adhesives, it is obvious that it is equally true of any system which applies accurate amounts of a liquid onto a work surface, such as lubricating fluids.